This section provides background information related to the present disclosure which is not necessarily prior art.
The WiMAX network is a wireless metropolitan area network based on IEEE 802.16 standard, which, as shown in FIG. 1 consists of a user terminal, an access service network (ASN) and a connectivity service network (CSN). In WiMAX, a user terminal is a mobile station (MS)/subscriber station (SS); an ASN includes base station (BS) and access service network gateway (ASN GW); a CSN includes logic entities, such as a policy function (PF) server, an authentication, authorization, accounting (AAA) server, and an application function (AF) server.
The ASN provides a set of network function for wireless access service to the user terminal. The BS is configured to:
provide a level two (L2) connection between the BS and the user terminal;
provide functions such as management, measure and power control of wireless resource, and compression and encoding of air interface data.
The ASN-GW is configured to:
provide client functions such as authentication, authorization, accounting of the user terminal, which are performed by an Anchor Authenticator functional entity and an Anchor Accounting Client functional entity respectively;
support network discovery and selection of Network Service Provider, NSP;
provide Relay function of level three (L3) information, such as IP address allocation, to the user terminal; and
manage wireless resource.
Besides the above-mentioned functions, the ASN-GW can also provide the following optional functions: ASN internal switch; paging and location management for the user terminal, such as a Paging Controller (PC) functional entity; tunnel management between ASN-GW that equals Foreign Agent (FA) in mobile IP (MIP) technique and Anchor PMIP Client) functional entity; Visitor Location registration, Anchor SFA functional entity.
Each of the above function corresponds to a functional entity in ASN-GW, for example, an Authenticator, a PMIP Client, an FA, a Paging Controller/Location Register (PC/LR), a Service Flow Authorization (SFA), a Data Pass Function (DPF), a Dynamic Host Configuration Protocol Proxy/Relay (DHCP Proxy/Relay), an Accounting Client, etc.
The functional entities in the above ASN-GW might have different timing for changing their triggering due to the functional entities that server individual user terminal move with the user terminals, resulting in the individual functional entity that serves particular user terminal might exist in different ASN-GWs. Thus, in the same service, the interaction between different ASN-GW's may occur, which would cause the implementing process of the service quite complex. For example, for an Accounting Client, since the user terminal moves, the accounting information will be transferred between multiple ASN-GW's. Then, except for the ASN-GW in which the Accounting Client acting as AAA Client is located is required to interact with AAA of accounting information, there also exists an interaction with ASN-GW in which the accounting agent that collects accounting information related to user service data process is located. However, the ASN-GW acting as the accounting agent that collects accounting information does not directly interact with the AAA server, but interacts with the ASN-GW in which the accounting client acting as AAA client is located.
Currently, there is no solution for shifting the ASN's functional entity in WiMAX network.